I think it is unlikely that earth is the only planet with life in the entire universe. As far as intelligent life I'm not sure but it seems to me that if intelligence can form on one planet the odds are good it could form on another planet. The real question for me is will we ever run across alien lifeforms? That seems very unlikely to me. I think the odds of actually finding another intelligent species in such a vast universe are fairly low considering our very limited degree of space travel. We haven't even managed to exit our solar system yet or get human beings to the nearest neighboring planet. So I don't think it really matters whether or not there is life out there as we will probably never meet it.
“Now I do not know whether I was then a man dreaming I was a butterfly, or whether I am now a butterfly, dreaming I am a man.” -Zhuangzi
“Though, as the crusade presses on, I find myself altogether incapable of staying here in saftey while others shed their blood for such a noble and just cause. For surely must the Almighty be with us even in the sundering of our nation. Our fight is for freedom, for liberty, and for all the principles upon which that aforementioned nation was built.” - Patrick “Madman of Galway” O'Dell
